“Blue light” sounds almost magical. But the effect of blue light exposure, emitted by LED-lit smartphones, tablets and flat screen TVs, is anything but. Study after study has found that this short-wave, high-energy illumination is a virtual sleep vampire, draining both the quality and quantity of our children’s rest.
Remember how you felt when you were a sleep-deprived new parent? Well, consider this: Kids who routinely use screens at bedtime may be feeling that way all the time. And you thought it was just hormones. (In fact, just the opposite is true: sleep deprivation can cause hormonal imbalances.)
It starts with moodiness and fuzzy thinking. But prolonged lack of quality sleep takes a direct hit on kids’ broader health and well being. In a raft of recent studies sleep disturbances have been linked, at least provisionally, to cancer, diabetes, heart disease, obesity, immune dysfunction, depression, ADHD and more.
That’s pretty terrifying. Especially when you consider how much we still don’t know about the connection between light and biology.
In 1981, Harvard Medical School researcher Dr. Charles Czeisler was the first to show that daylight keeps a person’s internal clock, or circadian rhythms, aligned with the environment. Exposure to any bright light at night, we now know, suppresses the secretion of the sleep-regulating hormone melatonin. And exposure to blue light does so roughly twice as powerfully.
One recent study of children aged six months to three years, conducted at the University of London, found that every hour of screen use stole a full 26 minutes of nighttime sleep. These toddlers also also took longer to fall asleep.
And by the way, there is nothing to suggest that adult sleepers fare differently. Screen usage by mums and dads today often tops nine hours a day, according to recent data from Family Zone. Less than a quarter of that is work-related. Tablets, laptops and smartphones - not to mention smart TVs - have become standard bedroom furniture in most parental bedrooms. Yet the research is clear: Being bathed in all that blue light at bedtime is a bit like winding down for the night with an ice-cold shower.
Blue light isn’t the only sleep vampire lurking in our devices. When your kids are online, they can easily lose track of time. So can you. That can mean bedtime gets delayed, leading to less time available for sleeping. And then there’s the matter of arousal. Quite simply, compelling content wakes us up - whether that means Club Penguin or Kylie Jenner’s Instagram feed - triggering emotions and altering hormone levels.
For all these reasons, M.I.T. psychologist Sherry Terkle, in her recent book, Reclaiming Conversation: The Power of Talk in the Digital Age, advises making all bedrooms tech-free “sacred spaces.”
Easier said than done? Perhaps - but Family Zone can help. Family Zone allows you to block content that may be keeping your kids up at night, and automatically switch off devices at the bedtimes you set.
What else can you do? Family Zone cyber expert Dr. Kristy Goodwin offers these tips for managing screentime to make sure your kids (and you!) get the sleep you need:
Online games like Fortnite, Minecraft and Roblox are fun for kids - and can stimulate creativity and collaboration. So where’s the danger ...